(1) Field of the Invention
The present invention provides a vehicle suspension system employing a beam mounted for pivoting movement to a hanger and connected securely to a vehicle axle where the beam is constructed with a laterally widening base as it extends longitudinally from the pivot mounting to the vehicle axle and with an axle shell securing the beam to the axle where the shell connection to the axle reduces stress on the vehicle axle.
(2) Description of the Related Art
In the design of vehicle suspension system beams of the type having a pivot mounting to a hanger member suspended beneath a vehicle chassis at one end, and a connection to a lateral vehicle axle and a spring means spanning between the beam and the vehicle chassis at an opposite end, it is desirable to reduce the weight of the beam without reducing its capacity to support vehicle loads. With the beam being a major component in most suspension systems, reduction of the beam's weight results in a significant reduction in the overall weight of the suspension system. However, in designing suspension beams to reduce their weight, care must be taken to avoid creating stress concentration areas in the beam itself or in its rigid connection to the vehicle axle. Difficulties are frequently encountered in the design of the connection between the beam and the vehicle axle where stresses are often concentrated. Load stresses due to vehicle load exerted on the beam and cyclic stresses exerted on the beam while the vehicle is operated over the road can be concentrated at the connection of the beam to the axle. Where the connection of the beam to the axle is a rigid, weld connection, the concentration of stresses on the weld can result in the weld's failure, causing the axle to separate from the beam and causing substantial damage to the vehicle.